The invention relates to a method for shipping a reel onboard a ship, where the reel is at least partly placed into a cargo space of the ship.
The invention also relates to an arrangement for shipping a reel onboard a ship, where the reel is at least partly placed into a cargo space of the ship.
The invention further relates to a tweendeck to be used as a transport support for a reel in sea transport.
The invention also relates to a tweendeck arrangement in a cargo space of the ship.
The invention is associated with shipping reels, particularly metal-band reels, onboard a ship. However, the method and arrangement of the invention can also be used for shipping different kinds of cylindrical goods.
Such reels are conventionally been transported at the bottom of the ship""s cargo space, meaning that the reels are placed directly at the bottom of the cargo space so as to be supported against the walls and the bottom of the cargo space. The reels are locked in relation to one another and also to be immovable regarding the ship by placing the reels on top of each other in such a manner that the reel on the topmost layer is supported on two reels on the layer below. In addition the reels are tied with disposable metal strips. The reels are also supported by pieces of wood.
One of the problems with this conventional arrangement is that the ship loaded with reels, using the conventional way, becomes too stable, and consequently the rolling period of the ship is short.
This is due to the fact that the metacentric height (GM) of the loaded ship is high. In other words the centre of gravity (G) of the loaded ship is relatively close to the bottom of the ship, as the heavy reels are placed at the bottom of the cargo space. The centre of gravity (G) of the loaded ship is therefore far from the metacentre (M) of the ship.
In the conventional arrangement the reels are difficult to place and to tie so that they remain immovably in position in the ship""s cargo space during transportation when the ship is subjected to rough seas. Since the metal band reels, in particular, are very heavy, the pieces of wood placed to support the reels are usually crushed when the metal band reels move.
The size of the reels, metal band reels in particular, is also increased. A metal band reel may weigh 30 to 35 tons. This may result in that the largest concentrated load allowed is exceeded at the bottom of the cargo space, since the surface of the metal band reel facing the bottom of the cargo space is generally small. As the reel size is increased it is not safe either to place locking reels between the reels in order to lock the reels in position.
It is an object of the invention to provide a method and an arrangement for shipping reels onboard a ship to solve the above problems.
The object of the invention is achieved with a method, characterized by using a reel holder, which holds the reel placed therein substantially in position at least in the horizontal and downward direction, and by the reel holder being arranged onto a tweendeck in the ship""s cargo space placed at a distance from the bottom of the ship""s cargo space, closer to the metacentre of the ship than to the bottom of the cargo space.
The arrangement of the invention is correspondingly characterized by comprising a reel holder, which holds the reel placed therein substantially in position at least in the horizontal and downward direction, and by the reel holder being arranged onto a tweendeck in the ship""s cargo space placed at a distance from the bottom of the ship""s cargo space, closer to the metacentre of the ship than to the bottom of the cargo space.
The invention also relates to a tweendeck to be used as a reel transport support for reels in sea transport, characterized by the tweendeck comprising at least one reel holder including means for preventing the reel from moving, said means being arranged to hold the reel placed in the reel holder substantially in position at least in the horizontal and downward direction, and by the tweendeck comprising means for placing the tweendeck in the ship""s cargo space at a distance from the bottom of the ship""s cargo space, closer to the metacentre of the ship than to the bottom of the ship.
The invention further relates to a tweendeck arrangement that is correspondingly characterized by comprising a tweendeck, which can be placed at a distance above the bottom of the cargo space, and by the tweendeck comprising at least one reel holder for a reel, and by the tweendeck arrangement comprising an arrangement for moving the tweendeck between a storage space and a second position, in which at least one reel can be placed into the reel holder.
The preferred embodiments of the invention are disclosed in the dependent claims.
The invention is based on the idea that heavy reels are placed closer to the metacentre of the ship, more precisely into the reel holders, which are placed on the tweendecks in the top part of the cargo space and which are closer to the metacentre of the ship than to the bottom of the cargo space, to reduce the metacentric height of the ship, since the centre of gravity of the loaded ship moves closer to the metacentre of the ship. As a result the pendulous motion of the ship is reduced and slows down. Simultaneously the strains placed upon the cargo are reduced.
As to the condition and logistics of the cargo the solution of the invention provides the advantage that an appropriate locking reel, which locks the reels to one another at the bottom of the ship""s cargo space when placing the reels onto the bottom of the ship, is left out, as the reels are placed into reel holders in the solution of the invention. This also accelerates the loading of the ship. A crane driver loading reels onto the ship and correspondingly unloading reels from the ship has an unobstructed visibility to the loading area, since the reel holders are clearly visible in the ship""s cargo space. To place the reels into the reel holders on the tweendecks can be carried out using a programmable crane and an automatic reel grip tong, thus reducing labour costs. The solution of the invention also accelerates the loading and unloading of the ship.
Since the position of an individual reel on a ship is known and the reels are placed into the reel holders, the reels can be removed from the ship in any order, for example in accordance with the wishes of the receiver.
The solution of the invention also provides such an advantage that the reel holders allow the reels to be fastened on the ship for example using such belts that can be used more than once.
The invention further provides such an advantage that the reels remain firmly in the reel holders without any additional supports, thus facilitating the loading and unloading of reels to and from the ship. Since the solution of the invention does not require disposable binders or timber, said solution is environmentally friendly.
In a preferred embodiment of the invention the reels are placed into such reel holders, which are arranged onto the tweendecks placed above the bottom of the ship""s cargo space and which are also placed beneath the weather deck of the cargo space. The weather deck is thus able to prevent the reels from being displaced from the reel holders. The reels need not therefore necessarily be separately fastened to the reel holders in this preferred embodiment. As the reels are placed between the tweendeck and the weather deck, they cannot move and are therefore unable to cause danger to the ship. The stevedores do not have to arrange reels or for example wedges or mats into the ship""s cargo space, since the reels are simply mounted to the reel holders and thereafter the weather deck is closed in such a manner that the reels remain in the reel holders without separate fastening elements. Since the reels are placed into the reel holders beneath the weather deck, there is no danger of the reels moving and possibly being damaged. As the reels are not separately fastened, the fastening material does not create any waste or expenses.
The solution of the invention also allows to use the ship""s cargo space more efficiently, as containers for example can be placed beneath the tweendeck of the ship""s cargo space and above the weather deck. The solution of the invention allows the cargo to be appropriately placed on the ship and the ship to be loaded and unloaded always in the same order. The receiver therefore knows in advance what and when cargo is unloaded from the ship. The unloading end can therefore be provided in advance with an appropriate number of suitable equipment. The same naturally applies to the loading end.
The solution of the invention provides economic and environmental advantages. The optimal metacentric height GM of a ship allows to select the route more appropriately, thus reducing petrol consumption and channel fees, for example.